from nose.tools import assert_equal, assert_raises, assert_not_equal
import networkx as nx
import io
import tempfile
import os
from networkx.readwrite.p2g import *
from networkx.testing import *


class TestP2G:

    def setUp(self):
        self.G=nx.Graph(name="test")
        e=[('a','b'),('b','c'),('c','d'),('d','e'),('e','f'),('a','f')]
        self.G.add_edges_from(e)
        self.G.add_node('g')
        self.DG=nx.DiGraph(self.G)

    def test_read_p2g(self):
        s = b"""\
name
3 4
a
1 2
b

c
0 2
"""
        bytesIO = io.BytesIO(s)
        G = read_p2g(bytesIO)
        assert_equal(G.name,'name')
        assert_equal(sorted(G),['a','b','c'])
        edges = [(str(u),str(v)) for u,v in G.edges()]
        assert_edges_equal(G.edges(),[('a','c'),('a','b'),('c','a'),('c','c')])

    def test_write_p2g(self):
        s=b"""foo
3 2
1
1 
2
2 
3

"""
        fh=io.BytesIO()
        G=nx.DiGraph()
        G.name='foo'
        G.add_edges_from([(1,2),(2,3)])
        write_p2g(G,fh)
        fh.seek(0)
        r=fh.read()
        assert_equal(r,s)

    def test_write_read_p2g(self):
        fh=io.BytesIO()
        G=nx.DiGraph()
        G.name='foo'
        G.add_edges_from([('a','b'),('b','c')])
        write_p2g(G,fh)
        fh.seek(0)
        H=read_p2g(fh)
        assert_edges_equal(G.edges(),H.edges())
